Semiconductor IC-embedded substrate and method for manufacturing same

ABSTRACT

A semiconductor IC-embedded substrate suitable for embedding a semiconductor IC in which the electrode pitch is extremely narrow. The substrate comprises a semiconductor IC  120  in which stud bumps  121  are provided to the principal surface  120   a,  a first resin layer  111  for covering the principal surface  120   a  of the semiconductor IC  120,  and a second resin layer  112  for covering the back surface  120   b  of the semiconductor IC  120.  The stud bumps  121  of the semiconductor IC  120  protrude from the surface of the first resin layer  111.  The method for causing the stud bumps  121  to protrude from the surface of the first resin layer  111  may involve using a wet blasting method to cause an overall reduction of the thickness of the first resin layer  111.  The stud bumps  121  can thereby be properly uncovered even when the electrode pitch of the semiconductor IC  120  is narrow.

TECHNICAL FIELD

The present invention relates to a semiconductor IC-embedded substrateand to a method for manufacturing the same, and particularly relates toa semiconductor IC-embedded substrate that is suitable for embedding asemiconductor IC in which the electrode pitch is extremely narrow, andto a method for manufacturing the same.

BACKGROUND OF THE INVENTION

Numerous proposals have been made in recent years for mounting asemiconductor IC on a printed circuit board in a bare-chip state inorder to satisfy the requirements of smaller size and thinner profilefor a semiconductor IC mounting module. A semiconductor IC in abare-chip state has an extremely narrow electrode pitch compared to apackaged semiconductor IC. Therefore, when a bare-chip semiconductor ICis mounted on a printed circuit board, a critical issue is the manner inwhich an electrode (hereinafter referred to as a “pad electrode”)provided to a semiconductor IC is connected to wiring (hereinafterreferred to as a “wiring pattern”) provided to the printed circuitboard.

Wire bonding is known as one method for connecting a pad electrode witha wiring pattern. This method allows a semiconductor IC in a bare-chipstate to be packaged with relative ease, but the region in which thesemiconductor IC is mounted must be in a different plane on thesubstrate from the region in which the bonding wire is connected. Thismethod therefore has drawbacks in that the package surface area isenlarged.

Other known methods for connecting a pad electrode to a wiring patterninclude a method whereby a flip-chip connection is made between aprinted circuit board and a semiconductor IC that is in a bare-chipstate. Although the size of the packaging area can be reduced by thismethod, this method has drawbacks in that a complicated process isinvolved in creating multiple layers of under barrier metal that must beformed on the surface of the pad electrode in order to adequatelymaintain the mechanical strength of the connection between the padelectrode and the wiring pattern.

Since both of the methods described above involve mounting asemiconductor IC on the surface of a printed circuit board, thedifficulty of reducing the thickness of the module as a whole is adrawback that is common to both methods. Methods for overcoming thisdrawback are described in Japanese Laid-open Patent Application Nos.H9-321408, 2002-246500, 2001-339165, 2002-50874, 2002-170840,2002-246507, and 2003-7896. In these methods, a cavity is formed in aprinted circuit board, a bare-chip semiconductor IC is embedded in thecavity, and a semiconductor IC-embedded substrate is formed thereby.

However, in the methods described in Japanese Laid-open PatentApplication Nos. H9-321408, 2002-246500, 2001-339165, 2002-50874,2002-170840, 2002-246507, and 2003-7896, the thickness of the printedcircuit board must be increased to a certain degree in order to maintainthe strength of the portion in which the cavity is formed. This increasein thickness is a drawback in that it interferes with reducing thethickness of the module. Furthermore, since the size of the cavity inits planar direction must be set so as to be somewhat larger than thesize of the semiconductor IC in its planar direction, the pad electrodeand the wiring pattern become misaligned with each other, and it istherefore extremely difficult to utilize a semiconductor IC that has anarrow electrode pitch of 100 μm or less.

Since each pad electrode is exposed by laser irradiation when asemiconductor IC is embedded, as the electrode pitch of thesemiconductor IC becomes narrower, even higher precision is required forthe process, and the processing time also increases in proportion to thenumber of pad electrodes. The diameter of a via formed by laserirradiation must also be reduced as the electrode pitch of thesemiconductor IC becomes narrower, and drawbacks therefore occur in thatit becomes difficult to perform desmearing of the inside of the via.

However, Japanese Laid-open Patent Application No. 2005-64470 disclosesa method whereby semiconductor IC is fixed to a transfer board, and inthis state, a post electrode provided to a printed circuit board isinserted in a positioning hole provided to the transfer board. Thesemiconductor IC is thereby embedded in an uncured or partially curedresin layer, and the pad electrode is then exposed by polishing orblasting. According to this method, not only can a semiconductor IC bepositioned with high precision, but it is also possible to overcome thedrawbacks described above that occur when each pad electrode is exposedby laser irradiation.

However, the method described in Japanese Laid-open Patent ApplicationNo. 2005-64470 has drawbacks in that constraints are imposed by therequirement that a post electrode be formed in advance on the printedcircuit board. Since a transfer board must also be manufactured, thismethod cannot be considered suitable for the manufacture of allsemiconductor IC-embedded substrates.

Although not related to methods for manufacturing a semiconductorIC-embedded substrate, examples of methods that use polishing orblasting to uncover an electrode provided to a semiconductor IC aredescribed in Japanese Laid-open Patent Application Nos. H11-274241,2001-250902, and 2003-197655.

SUMMARY OF THE INVENTION

Various drawbacks occur when the conventional methods are used to embeda semiconductor IC that has a narrow electrode pitch in a substrate. Thepresent invention was developed in order to overcome such drawbacks, andan object of the present invention is to provide a semiconductorIC-embedded substrate and manufacturing method that are suitable forembedding a semiconductor IC in which the electrode pitch is extremelynarrow.

The semiconductor IC-embedded substrate according to the presentinvention comprises a semiconductor IC in which conductive protrusionsare provided to a principal surface of the semiconductor IC, a firstresin layer for covering the principal surface of the semiconductor IC,and a second resin layer for covering a back surface of thesemiconductor IC, wherein the conductive protrusions of thesemiconductor IC protrude from a surface of the first resin layer. It ispreferred that at least one of layers selected from the first and secondresin layers be in contact with a side surface of the semiconductor IC.It is also preferred that the first resin layer be in contact with theprincipal surface of the semiconductor IC, and that the second resinlayer be in contact with the back surface of the semiconductor IC.

A die attach film may be provided to either the principal surface or theback surface of the semiconductor IC, and either the principal surfaceor the back surface of the semiconductor IC may be covered by one layerselected from the first and second resin layers via the die attach film.

It is preferred that the semiconductor IC-embedded substrate accordingto the present invention further comprise a through-electrode that isprovided through the first and second resin layers. It is more preferredthat the semiconductor IC be endowed with a thin profile.

It is preferred that the semiconductor IC-embedded substrate accordingto the present invention further comprise a wiring pattern formed on thesurface of the first resin layer and connected to the conductiveprotrusions, wherein a width of the wiring pattern on the conductiveprotrusions is smaller than a diameter of a protruding portions of theconductive protrusions.

The method for manufacturing a semiconductor IC-embedded substrateaccording to the present invention comprises a first step for inserting,between first and second resin layers, a semiconductor IC in whichconductive protrusions are provided to a principal surface; a secondstep for causing the conductive protrusions of the semiconductor IC toprotrude from a first surface of the first resin layer by reducing athickness of the first resin layer; and a third step for forming awiring pattern on the first surface of the first resin layer.

It is preferred that the second step comprise reducing a thickness bywet blasting one surface of the first resin layer.

It is also preferred that the first step include a step for stacking asecond surface of the first resin layer and the principal surface of thesemiconductor IC so as to face each other, and a step for stacking afirst surface of the second resin layer and a back surface of thesemiconductor IC so as to face each other. In this case, thesemiconductor IC is preferably mounted on the second surface of thefirst resin layer in the first step, based on alignment marks that areformed on the first surface or second surface of the first resin layer.

It is also preferred that the first step be performed in a state inwhich a first support substrate is affixed on a first side of the firstresin layer. It is more preferred in this case that a step for affixinga second support substrate on a second side of the second resin layer,and a step for peeling the first support substrate from a first side ofthe first resin layer be performed subsequent to the first step andprior to the second step.

The first step preferably includes a step for stacking a first surfaceof the second resin layer and a back surface of the semiconductor IC soas to face each other, and a step for stacking a second surface of thefirst resin layer and the principal surface of the semiconductor IC soas to face each other. It is preferred in this case that thesemiconductor IC be mounted on the first surface of the second resinlayer in the first step, based on alignment marks that are formed on thefirst surface or second surface of the second resin layer. It is morepreferred that the first step be performed in a state in which a secondsupport substrate is affixed on a second side of the second resin layer.

It is preferred that a width of the wiring pattern on the conductiveprotrusions be set in the third step so as to be smaller than a diameterof protruding portions of the conductive protrusions. It is alsopreferred that the method for manufacturing a semiconductor IC-embeddedsubstrate according to the present invention further comprise a fourthstep for forming a through-electrode that penetrates through the firstand second resin layers.

According to the present invention, the method for exposing conductiveprotrusions provided to a semiconductor IC involves reducing the overallthickness of the first resin layer by a wet blasting method or othermethod, rather than using laser irradiation. Therefore, the conductiveprotrusions can be properly uncovered even when the electrode pitch isnarrow. The protrusions can also be uncovered in a short time regardlessof the number of conductive protrusions. Since there is no smearing thatoccurs when a laser is used to form minute vias, the desmearing processmay also be omitted.

A highly precise mounting position can also be obtained by usingalignment marks as a positioning reference during mounting of thesemiconductor IC.

Setting the width of the wiring pattern formed on the first resin layerso as to be smaller than the diameter of the protruding portions of theconductive protrusions also makes it possible to prevent short-circuitdefects from occurring when the electrode pitch is particularly narrow.

These aspects of the present embodiment make it possible to overcome thevarious drawbacks that occur when conventional techniques are used toembed a semiconductor IC having a narrow electrode pitch into asubstrate.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and advantages of this inventionwill become more apparent by reference to the following detaileddescription of the invention taken in conjunction with the accompanyingdrawings, wherein:

FIG. 1 is a schematic sectional view showing the structure of asemiconductor IC-embedded substrate according to a first preferredembodiment of the present invention;

FIG. 2 is a schematic perspective view showing the structure of asemiconductor IC;

FIG. 3 is process diagram showing a process of forming an alignment markthat is a part of the manufacturing process of the semiconductorIC-embedded substrate shown in FIG. 1;

FIG. 4 is a process diagram showing a process of mounting thesemiconductor IC that is a part of the manufacturing process of thesemiconductor IC-embedded substrate shown in FIG. 1;

FIG. 5 is a process diagram showing a process of pressing a resin layerthat is a part of the manufacturing process of the semiconductorIC-embedded substrate shown in FIG. 1;

FIG. 6 is a process diagram showing a process of affixing a supportsubstrate that is a part of the manufacturing process of thesemiconductor IC-embedded substrate shown in FIG. 1;

FIG. 7 is a process diagram showing a process of peeling off the resinlayer that is a part of the manufacturing process of the semiconductorIC-embedded substrate shown in FIG. 1;

FIG. 8 is a process diagram showing a process of etching the resin layerthat is a part of the manufacturing process of the semiconductorIC-embedded substrate shown in FIG. 1;

FIG. 9 is a process diagram showing a process of forming through-holesthat is a part of the manufacturing process of the semiconductorIC-embedded substrate shown in FIG. 1;

FIG. 10 is a process diagram showing a process of forming a baseconductor layer that is a part of the manufacturing process of thesemiconductor IC-embedded substrate shown in FIG. 1;

FIG. 11 is a process diagram showing a process of affixing and exposingdry films that is a part of the manufacturing process of thesemiconductor IC-embedded substrate shown in FIG. 1;

FIG. 12 is a schematic plan view showing a positional relationshipbetween stud bumps and wiring pattern formation regions in case of A<B;

FIG. 13 is a schematic plan view showing a positional relationshipbetween stud bumps and wiring pattern formation regions in the casewhere significant misalignment occurs;

FIG. 14 is a schematic plan view showing a positional relationshipbetween stud bumps and wiring pattern formation regions in case of A>B;

FIG. 15 is a process diagram showing a process of forming wring patternsused to describe a method for manufacturing the semiconductorIC-embedded substrate shown in FIG. 1;

FIG. 16 is a process diagram showing a process of removing dry films andbase conductor layer that is a part of the manufacturing process of thesemiconductor IC-embedded substrate shown in FIG. 1;

FIG. 17 is a process diagram showing a process of pressing a resin layer(before pressing) that is a part of the manufacturing process of thesemiconductor IC-embedded substrate shown in FIG. 1;

FIG. 18 is a process diagram showing a process of pressing a resin layer(after pressing) that is a part of the manufacturing process of thesemiconductor IC-embedded substrate shown in FIG. 1;

FIG. 19 is a process diagram showing a process of peeling off thesupport substrate that is a part of the manufacturing process of thesemiconductor IC-embedded substrate shown in FIG. 1;

FIG. 20 is a process diagram showing a process of pressing another resinlayer (before pressing) that is a part of the manufacturing process ofthe semiconductor IC-embedded substrate shown in FIG. 1;

FIG. 21 is a process diagram showing a process of pressing another resinlayer (after pressing) that is a part of the manufacturing process ofthe semiconductor IC-embedded substrate shown in FIG. 1;

FIG. 22 is a process diagram showing a process of forming through-holesand a base conductor layer that is a part of the manufacturing processof the semiconductor IC-embedded substrate shown in FIG. 1;

FIG. 23 is a schematic sectional view showing the structure of asemiconductor IC-embedded substrate according to a second preferredembodiment of the present invention;

FIG. 24 is a process diagram showing a process of affixing a supportsubstrate that is a part of the manufacturing process of thesemiconductor IC-embedded substrate shown in FIG. 23;

FIG. 25 is a process diagram showing a process of forming alignmentmarks that is a part of the manufacturing process of the semiconductorIC-embedded substrate shown in FIG. 23;

FIG. 26 is a process diagram showing a process of forming a resin layerthat is a part of the manufacturing process of the semiconductorIC-embedded substrate shown in FIG. 23;

FIG. 27 is a process diagram showing a process of mounting asemiconductor IC that is a part of the manufacturing process of thesemiconductor IC-embedded substrate shown in FIG. 23;

FIG. 28 is a process diagram showing a process of pressing a resin layer(before pressing) that is a part of the manufacturing process of thesemiconductor IC-embedded substrate shown in FIG. 23;

FIG. 29 is a process diagram showing a process of pressing a resin layer(after pressing) that is a part of the manufacturing process of thesemiconductor IC-embedded substrate shown in FIG. 23;

FIG. 30 is a process diagram showing a process of etching the resinlayer that is a part of the manufacturing process of the semiconductorIC-embedded substrate shown in FIG. 23;

FIG. 31 is a process diagram showing a process of forming through-holesthat is a part of the manufacturing process of the semiconductorIC-embedded substrate shown in FIG. 23;

FIG. 32 is a process diagram showing a process of forming a baseconductor layer that is a part of the manufacturing process of thesemiconductor IC-embedded substrate shown in FIG. 23;

FIG. 33 is a process diagram showing a process of affixing and exposingdry films that is a part of the manufacturing process of thesemiconductor IC-embedded substrate shown in FIG. 23;

FIG. 34 is a process diagram showing a process of forming wring patternsused to describe a method for manufacturing the semiconductorIC-embedded substrate shown in FIG. 23;

FIG. 35 is a process diagram showing a process of removing dry films andbase conductor layer that is a part of the manufacturing process of thesemiconductor IC-embedded substrate shown in FIG. 23;

FIG. 36 is a process diagram showing a process of pressing a resin layer(before pressing) that is a part of the manufacturing process of thesemiconductor IC-embedded substrate shown in FIG. 23;

FIG. 37 is a process diagram showing a process of pressing a resin layer(after pressing) that is a part of the manufacturing process of thesemiconductor IC-embedded substrate shown in FIG. 23;

FIG. 38 is a process diagram showing a process of forming through-holesand a base conductor layer that is a part of the manufacturing processof the semiconductor IC-embedded substrate shown in FIG. 23;

FIG. 39 is a view used to describe the method for forming depressions inthe resin layer;

FIG. 40 is a view showing a state in which the semiconductor IC ismounted using as alignment marks the depressions provided to the resinlayer; and

FIG. 41 is a view showing a state in which the semiconductor IC ismounted to the resin layer by means of the die attach film.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Preferred embodiments of the present invention will now be explained indetail with reference to the drawings.

FIG. 1 is a schematic sectional view showing the structure of thesemiconductor IC-embedded substrate 100 according to a first preferredembodiment of the present invention.

As shown in FIG. 1, the semiconductor IC-embedded substrate 100according to the present embodiment is composed of layered resin layers111 through 114; a semiconductor IC 120 embedded between the resinlayers 111 and 112; alignment marks 130; various types of wiringpatterns 140, 150, 161, 162; and through-electrodes 152 and 163 through165. Stud bumps 121 that are a type of conductive protrusion are formedon pad electrodes (not shown in FIG. 1) of the semiconductor IC 120, andeach pad electrode is electrically connected to a wiring pattern 150 viathe corresponding stud bump 121. The stud bumps 121 protrude from thesurface of the resin layer 111, as shown in FIG. 1.

However, the conductive protrusions provided to the semiconductor IC 120in the present invention are not limited to being stud bumps, and platebumps, plating bumps, ball bumps, and various other types of bumps maybe used. When stud bumps are used as the conductive protrusions, thestud bumps may be formed by wire bonding of silver or copper. When platebumps are used, the plate bumps may be formed by plating, sputtering, orvapor deposition. When plating bumps are used, the bumps may be formedby plating. When ball bumps are used, the bumps may be formed by aprocess in which a solder ball is mounted on a land electrode and thenmelted, or cream solder is printed on a land electrode and then melted.The types of metals that can be used in the conductive protrusions arenot particularly limited, and examples of metals that can be usedinclude gold (Au), silver (Ag), copper (Cu), nickel (Ni), tin (Sn),chromium (Cr), nickel/chromium alloy (Ni—Cr), solder, and the like. Itis also possible to use conical bumps, cylindrical bumps, or bumpshaving another shape that are formed by screen printing and curing anelectrically conductive material; or bumps that are formed by printing ananopaste and sintering the nanopaste by heating.

The height of the stud bumps 121 and other conductive protrusions ispreferably set to about 5 to 200 μm, and a height of about 10 to 80 μmis particularly preferred. The reason for this is that when the heightis less than 5 μm, the resin layer 111 that covers the principal surface120 a of the semiconductor IC 120 is entirely removed in the stepdescribed hereinafter for uncovering the stud bumps 121, and there is arisk of damage to the principal surface 120 a of the semiconductor IC120. On the other hand, it is difficult to form conductive protrusionsthat are over 200 μm high, and a significant variation in height alsooccurs.

Although not shown in FIG. 1, a capacitor and other passive componentsmay be mounted to at least one of the wiring patterns 161, 162 of theoutermost layer.

In the semiconductor IC-embedded substrate 100 according to the presentembodiment, the embedded semiconductor IC 120 is reduced in thicknessthrough the use of polishing, whereby the overall thickness of thesemiconductor IC-embedded substrate 100 can be reduced to 1 mm or less,or to about 200 μm, for example. As will be described hereinafter, thesemiconductor IC 120 in the present embodiment is aligned with respectto the alignment marks 130. There is therefore an extremely lowoccurrence of misalignment between the positions of each stud bump 121in the planar direction and the relative positioning of each type ofwiring pattern 140, 150, 161 and 162.

FIG. 2 is a schematic perspective view showing the structure of thesemiconductor IC 120.

As shown in FIG. 2, the semiconductor IC 120 is in a bare-chip state,and numerous pad electrodes 121 a are provided to the principal surface120 a of the semiconductor IC. In the semiconductor IC-embeddedsubstrate 100 according to the present embodiment as describedhereinafter, since all of the stud bumps 121 are uncovered at once by awet blasting method, this process is free of the drawbacks of the priorart that occur when the pad electrodes are exposed by laser irradiation.Therefore, it is possible to use a semiconductor IC in which the pitch(electrode pitch) of the pad electrodes 121 a is extremely narrow, being100 μm or less, or 60 μm, for example. However, this configuration isnot limiting.

A back surface 120 b of the semiconductor IC 120 is polished, wherebythe thickness t (distance from the principal surface 120 a to the backsurface 120 b) of the semiconductor IC 120 is extremely small comparedto an ordinary semiconductor IC. The thickness t of the semiconductor IC120 is not particularly limited, but is preferably set to 200 μm orless, or about 20 to 100 μm, for example. It is preferred that the backsurface 120 b be polished for multiple semiconductor ICs at once whilein the wafer state, and the semiconductor ICs 120 be then separated fromeach other by dicing. When dicing is performed to separate individualsemiconductor ICs 120 prior to reducing the thickness by polishing,operational efficiency is improved by polishing the back surface 120 bin a state in which the principal surface 120 a of the semiconductor IC120 is covered by a heat-curable resin or the like.

In the present, invention, however, the method used to endow thesemiconductor IC 120 with a thin profile is not limited to polishing,and it is also possible to use a thickness-reducing method that involvesetching, plasma treatment, laser irradiation, or a blasting treatment,for example.

Stud bumps 121 are formed on the pad electrodes 121 a. The size of thestud bumps 121 may be appropriately set according to the electrodepitch. For example, when the electrode pitch is approximately 100 μm,the stud bumps 121 may have a diameter of about 30 to 80 μm and a heightof about 10 to 80 μm. The stud bumps 121 may be formed on the padelectrodes 121 a by using a wire bonder after the individualsemiconductor ICs 120 are separated by dicing. The material used to formthe stud bumps 121 is not particularly limited, but the use of copper(Cu) is preferred. When copper (Cu) is used as the material for formingthe stud bumps 121, a high-strength bond to the pad electrodes 121 a canbe obtained, and reliability is enhanced in comparison to a case inwhich gold (Au) is used.

In the semiconductor IC-embedded substrate 100 according to the presentembodiment as shown in FIG. 1, the principal surface 120 a of thesemiconductor IC 120 is directly covered by the resin layer 111, and theback surface 120 b of the semiconductor IC 120 is directly covered bythe resin layer 112. The stud bumps 121 of the semiconductor IC 120protrude from the surface of the resin layer 111, and are connected tothe wiring pattern 150 by the protruding portions thereof.

A metal layer 122 is formed on the back surface 120 b of thesemiconductor IC 120. The metal layer 122 functions as a dissipationpathway for heat generated by the operation of the semiconductor IC 120,and more effectively prevents cracking from occurring in the backsurface 120 b of the semiconductor IC 120. The metal layer 122 alsoserves to enhance the handling properties of the semiconductor IC 120.

A through-electrode 165 provided so as to penetrate through the resinlayers 112, 114 connects the metal layer 122 to a wiring pattern 162formed on the outermost layer. Since the through-electrode 165 functionsas a dissipation pathway for heat generated by the semiconductor IC 120,heat can be released to a motherboard with extremely high efficiency.Therefore, although the type of semiconductor IC 120 is not particularlylimited, it is possible to select as the semiconductor IC 120 a digitalIC that has an extremely high operating frequency, such as a CPU or DSP.

The material used to form the resin layers 111 through 114 may be aheat-curable resin or a thermoplastic resin insofar as the material hasreflow resistance. Specific materials that may be selected include epoxyresins, bismaleimide triazine resins (BT resin), phenol resins, vinylbenzyl resins, polyphenylene ether (polyphenylene ether oxide) resins(PPE, PPO), cyanate resins, benzoxazine resins, polyimide resins,aromatic polyester resins, polyphenylene sulfide resins, polyether imideresins, polyarylate resins, polyester ether ketone resins, and the like.It is also possible to use a material in which a nonwoven cloth formedfrom glass cloth, aramid fibers, an aromatic polyester, or the like isimpregnated with a resin described above, or a material in which afiller is added to a resin described above.

The method for manufacturing the semiconductor IC-embedded substrate 100shown in FIG. 1 will next be described with reference to the drawings.

FIGS. 3 through 22 are process diagrams used to describe the method formanufacturing the semiconductor IC-embedded substrate 100 shown in FIG.1.

First, a resin layer 111 is prepared on which alignment marks 130 areformed, and a support substrate 181 is affixed to the resin layer 111,as shown in FIG. 3. The alignment marks 130 may be formed by patterninga conductive layer that is formed on the surface of the resin layer 111,or may be formed on the surface of the resin layer 111 by a transfermethod. Regardless of which of these methods is used, the alignmentmarks 130 are used to position the semiconductor IC 120, making itnecessary to properly control the position in which the alignment marks130 are formed. The alignment marks 130 may be substituted by an actualwiring pattern, or may be a pattern used exclusively for alignment.

The material used to form the support substrate 181 is not particularlylimited, and it is possible to use nickel (Ni) or stainless steel, forexample. The thickness of the support substrate 181 is not particularlylimited insofar as the necessary mechanical strength is ensured, and thethickness may be set to about 50 to 2,000 μm, for example. On the otherhand, the resin layer 111 must have a thickness that is at least greaterthan the height of the stud bumps 121.

The semiconductor IC 120 is then mounted on the surface of the resinlayer 111 while being positioned using the alignment marks 130, as shownin FIG. 4. In the present embodiment, the semiconductor IC 120 ismounted face-down, or with the principal surface 120 a facing downward.When a heat-curable resin is used as the resin layer, the resin layer111 is melted at this time by heating. When a thermoplastic resin isused as the resin layer, the stud bumps 121 sink into the resin layer111 due to the elasticity of the thermoplastic resin. The semiconductorIC 120 is thereby temporarily fixed to the resin layer 111. The resinlayer 111 and the principal surface 120 a of the semiconductor IC 120are also in contact with each other. When the material used to form theresin layer 111 is a heat-curable resin, complete fixing is achieved byheating the assembly. When a thermoplastic resin is used, fixing isachieved by heating/melting to increase adhesion.

A layered sheet composed of a conductor layer 140 a and a resin layer112 in an uncured or partially cured state is then stacked so that theresin layer 112 and the back surface 120 b of the semiconductor IC 120face each other, and the assembly is pressed together while beingheated, as shown in FIG. 5. The resin layer 112 is thereby cured, and astate occurs in which the back surface 120 b and side surface 120 c ofthe semiconductor IC 120 are completely covered by the resin layer 112,as shown in FIG. 6. When the material forming the resin layer 112 is athermoplastic material, the same state is attained by hot-pressing theassembly after the stacking step. In other words, a state occurs at thistime in which the semiconductor IC 120 is held between the resin layers111 and 112.

As shown in FIG. 6, another support substrate 182 is then affixed to thesurface on the opposite side from the support substrate 181 as viewedfrom the semiconductor IC 120. After the other support substrate 182 isaffixed in this manner, the support substrate 181 that was affixedearlier is peeled off, as shown in FIG. 7.

The surface of the resin layer 111 is then etched using a wet blastingmethod, as shown in FIG. 8. The etching rate in the wet blasting methodvaries according to the malleability of the material being etched.Specifically, the etching rate is high for a material (cured resin orthe like) that has relatively low malleability, and the etching rate islow for a material (metal or the like) that has relatively highmalleability. Therefore, when the surface of the resin layer 111 isetched by a wet blasting method, the stud bumps 121 provided to thesemiconductor IC 120 can be caused to protrude from the surface of theresin layer 111 by adjusting the etching rate/etching conditions. Theamount of protrusion is not particularly limited, but is preferably setto about 0.1 to 20 μm.

The method used to reduce the thickness of the resin layer 111 is notlimited to a wet blasting method, and a dry blasting method, an ionmilling method, a plasma etching method, or another etching method maybe used. However, a wet blasting method has high precision and excellentworking efficiency, and enables an adequate selection ratio to bemaintained, and is therefore greatly preferred for use. Polishing thatuses a buffer or the like is unsuitable as the method for reducing thethickness of the resin layer 111 in the present invention. The reasonfor this is that in polishing using a buffer or the like, the stud bumps121 and the resin layer 111 are in the same plane, and not only is itimpossible for the stud bumps 121 to protrude, but certain polishingconditions can also cause the conductive material that constitutes thestud bumps 121 to form a line in the rotation direction, which can causea short circuit.

Since the method for exposing the stud bumps 121 involves an overallreduction of the thickness of the resin layer 111 by wet blasting oranother method, and not forming a laser via in the resin layer 111 byconventional laser irradiation, the stud bumps 121 can be properlyuncovered all at once even when the electrode pitch is narrow.

As shown in FIG. 9, through-holes 112 a that penetrate through the resinlayers 111 and 112 are then formed by laser irradiation from thedirection of the resin layer 111. However, a method other than laserirradiation may also be used to form the through-holes 112 a.

As shown in FIG. 10, a sputtering method or other vapor-phase growthmethod is used to form a thin base conductor layer 151 on the entiresurface of the resin layer 111 including the insides of thethrough-holes 112 a. The protruding portions of the stud bumps 121 andthe portions of the conductor layer 140 a that are exposed at thebottoms of the through-holes 112 a are thereby directly covered by thebase conductor layer 151. However, an electroless plating method or avapor deposition method may be used instead of vapor-phase growth toform the base conductor layer 151. Since the unnecessary portion of thebase conductor layer 151 is subsequently removed, the base conductorlayer 151 must have an adequately small thickness of about 0.005 to 3μm, or preferably 0.3 to 2 μm, for example.

In the present embodiment, since the stud bumps 121 protrude from thesurface of the resin layer 111, there is no need to remove etchingresidue or perform other pre-processing prior to forming the baseconductor layer 151. In other words, when the stud bumps 121 and theresin layer 111 are in the same plane, the surfaces of the stud bumps121 can become covered by etching residue, and conduction defects canoccur if the base conductor layer 151 is formed in this state. Incontrast, a wet blasting treatment is performed in the presentembodiment under conditions whereby the stud bumps 121 protrude from thesurface of the resin layer 111. Since the etching residue is therebyreliably removed from the surfaces of the stud bumps 121, the baseconductor layer 151 can be formed without any preprocessing.

Light-sensitive dry films 101, 102 are then affixed to both surfaces ofthe substrate, i.e., to the surface of the base conductor layer 151 andthe surface of the support substrate 182, as shown in FIG. 11. The dryfilms 101 are then exposed using a photomask not shown in the drawing,and the dry films 101 are removed from the regions 150 a in which thewiring pattern 150 is to be formed. The base conductor layer 151 isthereby exposed in the regions 150 a in which the wiring pattern 150 isto be formed.

The dry film 102 is not removed at this time, thus maintaining a statein which the entire surface of the support substrate 182 is essentiallycovered. The thickness of the dry films 101 must be set so as to besomewhat greater than that of the wiring pattern 150. When the thicknessof the wiring pattern 150 is about 20 μm, for example, the thickness ofthe dry films 101 may be set to about 25 μm. The dry film 102, however,is provided for the purpose of preventing the surface of the supportsubstrate 182 from being plated, and may have any thickness.

As shown in FIG. 11, regions that correspond to the stud bumps 121 areincluded in the regions 150 a in which the wiring pattern 150 is to beformed. When a semiconductor IC 120 having an extremely narrow electrodepitch is used, there is no allowance for significant misalignment of thepositions of the stud bumps 121 and the regions 150 a relative to eachother in the planar direction. However, in the present embodiment, sincethe semiconductor IC 120 is aligned with respect to the alignment marks130, it is possible to minimize misalignment between the positions ofthe stud bumps 121 and the positions of the regions 150 a in the planardirection.

In the example shown in FIG. 11, the width of the regions 150 a in whichthe wiring pattern 150 is to be formed is set so as to be larger thanthe diameter of the stud bumps 121. However, when the electrode pitch isparticularly narrow, a manufacturing margin can be maintained by settingthe width of the wiring pattern 150 formation regions 150 a so as to besmaller than the diameter of the stud bumps 121.

In other words, as shown in the schematic plan view of FIG. 12, when A<Bor A=B (where A is the diameter of the protruding portions of the studbumps 121, and B is the width of the wiring pattern 150 formationregions 150 a), two stud bumps 121 are included within a single region150 a when there is significant misalignment during patterning of thedry films 101, as shown in FIG. 13. When this type of misalignmentoccurs, these two stud bumps 121 are ultimately connected by the wiringpattern 150, and a short-circuit defect therefore occurs.

This type of problem is overcome by setting A>B (where A is the diameterof the protruding portions of the stud bumps 121, and B is the width ofthe wiring pattern 150 formation regions 150 a), as shown in FIG. 14.This configuration makes it possible to reduce the likelihood of twostud bumps 121 being included within a single region 150 a, even whenthere is some misalignment during patterning of the dry films 101.Specifically, the margin is enlarged by an amount commensurate with thedistance given by A−B, in comparison to a case in which A=B.Accordingly, setting the width B of the regions 150 a so that B<A−X(where X is the achievable margin) is satisfied makes it possible toreliably prevent a short circuit between adjacent stud bumps 121.

However, adopting the setting of A>B is not essential to the presentinvention, and a setting of A<B or A=B is also possible, as in theexample shown in FIG. 12.

After a portion of the base conductor layer 151 is exposed in thismanner, electroplating is performed using the base conductor layer 151as the base, as shown in FIG. 15. The wiring pattern 150 is therebyformed in the regions 150 a in which the base conductor layer 151 isexposed. Accordingly, when the width of the regions 150 a is set to B,the width of the wiring pattern 150 thus formed is also B. The insidesof the through-holes 112 a are also filled by through-electrodes 152. Inother words, the through-electrodes 152 penetrate through the resinlayers 111, 112, whereby the conductor layer 140 a and the wiringpattern 150 are connected to each other via the through-electrodes 152.Since the entire surface of the support substrate 182 is essentiallycovered by the dry film 102, there is no plating formed on the supportsubstrate 182.

The type of plating solution may be appropriately selected according tothe material used to form the wiring pattern 150 and thethrough-electrodes 152. When the material forming these components iscopper (Cu), for example, a copper sulfate solution may be used as theplating solution.

The dry films 101, 102 are then peeled off, and the unnecessary baseconductor layer 151 in the portion in which the wiring pattern 150 isnot formed is also removed (soft etched) using acid or another etchingsolution, as shown in FIG. 16.

A layered sheet composed of a resin layer 113 and a conductor layer 171is then pressed and heated, as shown in FIG. 17. The wiring pattern 150and the resin layer 111 are thereby covered by the resin layer 113, inthe state shown in FIG. 18.

The support substrate 182 that was affixed later is then peeled off, andthe exposed conductor layer 140 a is patterned to form a wiring pattern140, as shown in FIG. 19.

A layered sheet composed of a resin layer 114 and a conductor layer 172is then pressed and heated, as shown in FIG. 20. The wiring pattern 140and the resin layer 112 are thereby covered by the resin layer 114 inthe state shown in FIG. 21.

After the conductor layers 171 and 172 are then removed or made thinner,through-holes 113 a, 114 a and 114 b are formed by laser irradiation oranother method, as shown in FIG. 22. The through-hole 113 a penetratesthrough the resin layer 113 to expose the wiring pattern 150, thethrough-hole 114 a penetrates through the resin layer 114 to expose thewiring pattern 140, and the through-hole 114 b penetrates through theresin layers 114 and 112 to expose the metal layer 122.

A thin base conductor layer 160 is formed on the entire surface,including the insides of the through-holes 113 a, 114 a, 114 b, and thesame step as the step described using FIGS. 11, 15, and 16 is thenperformed to form wiring patterns 161 and 162 on the outermost surfaceshown in FIG. 1. In this step, the inside of the through-hole 113 a isfilled by a through-electrode 163, whereby the wiring pattern 161 andthe wiring pattern 150 are connected to each other. The inside of thethrough-hole 114 a is also filled by a through-electrode 164, wherebythe wiring pattern 162 and the wiring pattern 140 are connected to eachother. Furthermore, the inside of the through-hole 114 b is filled by athrough-electrode 165, whereby the wiring pattern 162 and the wiringpattern 122 are connected to each other.

The semiconductor IC-embedded substrate 100 shown in FIG. 1 is therebycompleted.

In the present embodiment as described above, the method for exposingthe stud bumps 121 involves reducing the overall thickness of the resinlayer 111 by a wet blasting method or other method, rather than usinglaser irradiation. Therefore, the stud bumps 121 can be properlyuncovered even when the electrode pitch is narrow. The stud bumps 121can also be uncovered in a short time regardless of the number of studbumps 121. Since there is no smearing that occurs when a laser is usedto form minute vias, the desmearing process may also be omitted.

In the present embodiment in particular, a wet blasting method is usedas the method for uncovering the stud bumps 121, and the stud bumps 121can be caused to protrude from the surface of the resin layer 111 byadjusting the etching rate/etching conditions. There is therefore noneed to remove etching residue or perform other pre-processing prior toforming the base conductor layer 151.

Furthermore, since alignment marks 130 formed on the surface of theresin layer 111 are used as a positioning reference when thesemiconductor IC 120 is mounted, a highly precise mounting position canbe obtained.

Adopting these aspects of the configuration of the present embodimentmakes it possible to overcome the various drawbacks of the prior artthat are encountered when a semiconductor IC having a narrow electrodepitch is embedded in a substrate. In the present embodiment, since thesemiconductor IC 120 is mounted face-down, the IC can be mounted whilean image of the stud bumps 121 is formed from below. It is thereforepossible to obtain extremely high precision in the mounting position.

Since the thickness t of the semiconductor IC 120 used in the presentembodiment is made extremely low by polishing or the like, thesemiconductor IC-embedded substrate 100 as a whole is extremely thin andhas a thickness of about 200 μm, for example.

In most of the sequence of steps in the present embodiment, the processis carried out while the substrate being worked is held by the supportsubstrate 181 and support substrate 182. The ease of handling istherefore enhanced, and it is possible to reduce loads placed on thesemiconductor IC 120 due to cracking, fragmentation, and deformation ofthe substrate. It is also possible to prevent dimensional variation anddistortion of the substrate during patterning. It is thereby possible tominimize distortion or misalignment between the stud bumps 121 and thewiring pattern 150, and to increase the stability of connections betweenthese components.

When the width (B) of the wiring pattern 150 is set so as to be smallerthan the diameter (A) of the protruding portions of the stud bumps 121,short-circuit defects can be prevented even when the electrode pitch isparticularly narrow. This configuration is difficult to adopt when amethod is used in which the stud bumps 121 are exposed by laserirradiation. A significant advantage is therefore gained in the presentembodiment by uncovering the stud bumps 121 using a wet blasting method.

In other words, in a method for exposing the stud bumps 121 by laserirradiation, the limit to which the size of the laser aperture can bereduced is about 50 μm to 80 μm. Since misalignment inevitably occursduring laser irradiation, it is practically impossible to properlyexpose only the desired stud bumps 121 by using laser irradiation whenthe diameter of the stud bumps 121 is about 50 to 60 μm, for example. Ina case in which the wiring pattern 150 is formed using a semi-additivemethod after vias are formed by a laser, problems occur in the abilityto expose, develop, and peel off the dry films when an attempt is madeto set the width (B) of the wiring pattern 150 at or below the diameterof the vias, and it becomes impossible to form the correct pattern. Alsowhen a subtractive method is used, the plating inside the vias isetched, and open circuit defects occur when the width (B) of the wiringpattern 150 is made smaller than the diameter of the vias.

Setting the width (B) of the wiring pattern 150 so as to be smaller thanthe diameter of the stud bumps 121 is thus extremely problematic whenlaser irradiation is used as the method for exposing the stud bumps 121.However, since a wet blasting method is used to uncover the stud bumps121 in the present embodiment, problems such as those described above donot occur, and it is possible to set the width (B) of the wiring pattern150 so as to be smaller than the diameter (A) of the protruding portionsof the stud bumps 121.

The semiconductor IC-embedded substrate according to a second preferredembodiment of the present invention will next be described.

FIG. 23 is a schematic sectional view showing the structure of thesemiconductor IC-embedded substrate 200 according to a second preferredembodiment of the present invention.

As shown in FIG. 23, the semiconductor IC-embedded substrate 200according to the present embodiment is composed of layered resin layers211 through 214; a semiconductor IC 220 embedded between resin layer 211and resin layer 212; alignment marks 230; various types of wiringpatterns 250, 261, 262; and through-electrodes 252 and 263 through 265.The semiconductor IC 220 has the same structure as the semiconductor IC120 shown in FIG. 2. Also in the present embodiment, stud bumps 221protrude from the surface of the resin layer 211, and are electricallyconnected to the wiring pattern 250 by the protruding portions thereof.

A capacitor and other passive components may also be mounted to at leastone of the wiring patterns 261, 262 of the outermost layer in thepresent embodiment. The material used to form the resin layers 211through 214 may be the same as the material used to form the resinlayers 111 through 114 in the abovementioned first embodiment.

The method for manufacturing the semiconductor IC-embedded substrate 200shown in FIG. 23 will next be described with reference to the drawings.

FIGS. 24 through 38 are process diagrams used to describe the method formanufacturing the semiconductor IC-embedded substrate 200 shown in FIG.23.

First, a resin layer 213 is prepared in which conductor layers 230 a,271 are formed on both surfaces, and a support substrate 281 is affixedto this resin layer 213 as shown in FIG. 24.

As shown in FIG. 25, the conductor layer 230 a is then patterned to formalignment marks 230. The alignment marks 230 in the present embodimentform a pattern that is also used as an actual wiring pattern.

As shown in FIG. 26, a resin layer 212 is then formed that covers theresin layer 213 and the alignment marks 230.

The semiconductor IC 220 is then mounted on the surface of the resinlayer 212 while being positioned using the alignment marks 230, as shownin FIG. 27. In the present embodiment, the semiconductor IC 220 ismounted face-up, or with the principal surface 220 a facing upward. Theback surface 220 b of the semiconductor IC 220 is thereby completelycovered by the resin layer 212.

A layered sheet composed of a resin layer 211 and a conductor layer 270is then stacked so that the resin layer 211 and the principal surface220 a of the semiconductor IC 220 face each other, and the assembly ispressed together while being heated, as shown in FIG. 28. This processcreates a state in which the principal surface 220 a and side surface220 c of the semiconductor IC 220 are completely covered by the resinlayer 211, as shown in FIG. 29. In other words, a state occurs at thistime in which the semiconductor IC 220 is held between the resin layers211 and 212.

The surface of the resin layer 211 is then etched using a wet blastingmethod or other method after the conductor layer 270 is removed, asshown in FIG. 30. The stud bumps 221 provided to the semiconductor IC220 are then caused to protrude from the surface of the resin layer 211by adjusting the etching rate/etching conditions in the same manner asin the embodiment described above.

As shown in FIG. 31, through-holes 211 a that penetrate through theresin layers 211, 212 are then formed by laser irradiation from thedirection of the resin layer 211. However, a method other than laserirradiation may also be used to form the through-holes 211 a.

As shown in FIG. 32, a sputtering method or other vapor-phase growthmethod is used to form a thin base conductor layer 251 on the entiresurface of the resin layer 211, including the insides of thethrough-holes 211 a. The protruding portions of the stud bumps 221 andthe portions of the alignment marks 230 that are exposed at the bottomsof the through-holes 211 a are thereby directly covered by the baseconductor layer 251. Since a wet blasting treatment is also used in thepresent embodiment to cause the stud bumps 221 to protrude from thesurface of the resin layer 211, there is no need to remove etchingresidue or perform other preprocessing before forming the base conductorlayer 251.

Light-sensitive dry films 201, 202 are then affixed to both surfaces ofthe substrate, i.e., to the surface of the base conductor layer 251 andthe surface of the support substrate 281, as shown in FIG. 33. The dryfilms 201 are then exposed using a photomask not shown in the drawing,and the dry films 201 are removed from the regions 250 a in which thewiring pattern 250 is to be formed. The base conductor layer 251 isthereby exposed in the regions 250 a in which the wiring pattern 250 isto be formed. The dry film 202 is not removed at this time, thusmaintaining a state in which the entire surface of the support substrate281 is essentially covered.

As shown in FIG. 33, regions that correspond to the stud bumps 221 arealso included in the present embodiment in the regions 250 a in whichthe wiring pattern 250 is to be formed. However, since the position ofthe semiconductor IC 220 is aligned with respect to the alignment marks230, there is little misalignment in the planar direction of thepositions of the stud bumps 221 and the regions 250 a in relation toeach other.

When the electrode pitch herein is particularly narrow, the relation A>Bis preferred, where A is the diameter of the protruding portions of thestud bumps 221, and B is the width of the regions 250 a in which thewiring pattern 250 is to be formed.

After a portion of the base conductor layer 251 is exposed in thismanner, electroplating is performed using the base conductor layer 251as the base, as shown in FIG. 34. The wiring pattern 250 is therebyformed in the regions 250 a in which the base conductor layer 251 isexposed. Accordingly, when the width of the regions 250 a is set to B,the width of the wiring pattern 250 thus formed is also B. The insidesof the through-holes 211 a are also filled by through-electrodes 252. Inother words, the through-electrodes 252 penetrate through the resinlayers 211, 212, whereby the alignment marks 230 and the wiring pattern250 are connected to each other via the through-electrodes 252. Sincethe entire surface of the support substrate 281 is essential covered bythe dry film 202, there is no plating formed on the support substrate281.

The dry films 201, 202 are then peeled off, and the unnecessary baseconductor layer 251 in the portion in which the wiring pattern 250 isnot formed is also removed (soft etched) using acid or another etchingsolution, as shown in FIG. 35.

A layered sheet composed of a resin layer 214 and a conductor layer 272is then pressed and heated, as shown in FIG. 36. The wiring pattern 250and the resin layer 211 are thereby covered by the resin layer 214, inthe state shown in FIG. 37. The support substrate 281 is then peeledoff.

After the conductor layers 271 and 272 are then removed or made thinner,through-holes 213 a, 213 b and 214 a are formed by laser irradiation oranother method, as shown in FIG. 38. The through-hole 213 a penetratesthrough the resin layer 213 to expose the alignment marks 230, thethrough-hole 213 b penetrates through the resin layers 213, 212 toexpose the metal layer 222, and the through-hole 214 a penetratesthrough the resin layer 214 to expose the wiring pattern 250.

A thin base conductor layer 260 is formed on the entire surface,including the insides of the through-holes 213 a, 213 b, 214 a, and thesame step as the step described using FIGS. 33 through 35 is thenperformed to form wiring patterns 261, 262 on the outermost surfaceshown in FIG. 23. In this step, the inside of the through-hole 213 a isfilled by a through-electrode 263, whereby the wiring pattern 261 andthe alignment marks 230 are connected to each other. The inside of thethrough-hole 213 b is also filled by a through-electrode 264, wherebythe wiring pattern 262 and the metal layer 222 are connected to eachother. Furthermore, the inside of the through-hole 214 a is filled by athrough-electrode 265, whereby the wiring pattern 262 and the wiringpattern 250 are connected to each other.

The semiconductor IC-embedded substrate 200 shown in FIG. 23 is therebycompleted.

As described above, the overall thickness of the resin layer 211 is alsoreduced in the present embodiment by a wet blasting method or othermethod, whereby the stud bumps 221 are caused to protrude from thesurface of the resin layer 211. It is therefore possible to obtain thesame effects as those of the first embodiment. Since the semiconductorIC 220 is mounted face-up in the present embodiment, only one supportsubstrate 281 is needed, and there is no need to affix another supportsubstrate during the process. Deformation of the substrate and otherdefects can therefore be prevented by a simpler process.

The present invention is in no way limited to the aforementionedembodiments, but rather various modifications are possible within thescope of the invention as recited in the claims, and naturally thesemodifications are included within the scope of the invention.

For example, a conductor pattern is used as an alignment marking in thefirst and second embodiments described above, but the alignment marksare not limited to being composed of a conductor pattern, anddepressions or the like provided to a resin layer may also be used asthe alignment marks. In one possible example, depressions 130 a areformed in a resin layer 111 by pressing using a die 301 that hasprotrusions 302, as shown in FIG. 39. A semiconductor IC 120 is thenmounted using the depressions 130 a as alignment marks, as shown in FIG.40.

In the first embodiment, the alignment marks 130 are provided to thesurface of the resin layer 111 on the side on which the semiconductor IC120 is mounted. However, this configuration does not limit thepositioning of the alignment marks 130, and the alignment marks 130 mayalso be provided to the surface on the opposite side of the resin layer111, for example. Similarly in the second embodiment, the alignmentmarks 230 are provided to the opposite surface of the resin layer 212from the side on which the semiconductor IC 220 is mounted. However,this configuration does not limit the positioning of the alignment marks230, and the alignment marks 230 may also be provided to the surface onthe opposite side of the resin layer 212, for example.

The semiconductor IC is also mounted directly on a resin layer in thefirst and second embodiments described above, but it is also possible toprovide a die attach film to the semiconductor IC and to mount thesemiconductor IC to a resin layer via the die attach film. In onepossible example, a die attach film 229 is provided to the back surfaceof the semiconductor IC 220 as shown in FIG. 41, and the semiconductorIC 220 is temporarily fixed to the resin layer 212 by bonding the dieattach film 229 and the resin layer 212. In this case, there is no needfor the resin layer 212 to have adhesive properties. In the case of theexample shown in FIG. 42, a die attach film 229 is interposed betweenthe resin layer 212 and the back surface 220 b of the semiconductor IC220 (*2), and these two components are therefore no longer in directcontact with each other. However, the back surface 220 b of thesemiconductor IC 220 (*2) is then covered by the resin layer 212 via thedie attach film 229.

1. A semiconductor IC-embedded substrate, comprising: a semiconductor ICin which conductive protrusions are provided to a principal surface ofthe semiconductor IC; a first resin layer for covering the principalsurface of the semiconductor IC; and a second resin layer for covering aback surface of the semiconductor IC, wherein the conductive protrusionsof the semiconductor IC protrude from a surface of the first resinlayer.
 2. The semiconductor IC-embedded substrate as claimed in claim 1,wherein at least one of the first and second resin layers is in contactwith a side surface of the semiconductor IC.
 3. The semiconductorIC-embedded substrate as claimed in claim 1, wherein the first resinlayer is in contact with the principal surface of the semiconductor IC;and the second resin layer is in contact with the back surface of thesemiconductor IC.
 4. The semiconductor IC-embedded substrate as claimedin claim 1, further comprising a die attach film provided to one surfaceselected from the principal surface and the back surface of thesemiconductor IC, the one surface selected from the principal surfaceand the back surface of the semiconductor IC is covered by one layerselected from the first and second resin layers via the die attach film.5. The semiconductor IC-embedded substrate as claimed in claim 1,further comprising a through-electrode that is provided through thefirst and second resin layers.
 6. The semiconductor IC-embeddedsubstrate as claimed in claim 1, further comprising a wiring patternformed on the surface of the first resin layer and connected to theconductive protrusions, a width of the wiring pattern on the conductiveprotrusions is smaller than a diameter of a protruding portion of theconductive protrusions.
 7. The semiconductor IC-embedded substrate asclaimed in claim 1, wherein the semiconductor IC is thinned.
 8. A methodfor manufacturing a semiconductor IC-embedded substrate, comprising: afirst step for inserting, between first and second resin layers, asemiconductor IC in which conductive protrusions are provided to aprincipal surface; a second step for causing the conductive protrusionsof the semiconductor IC to protrude from a first surface of the firstresin layer by reducing a thickness of the first resin layer; and athird step for forming a wiring pattern on the first surface of thefirst resin layer.
 9. The method for manufacturing a semiconductorIC-embedded substrate as claimed in claim 8, wherein the second step isperformed by reducing a thickness by wet blasting the first surface ofthe first resin layer.
 10. The method for manufacturing a semiconductorIC-embedded substrate as claimed in claim 8, wherein the first stepincludes: a step for stacking a second surface of the first resin layerand the principal surface of the semiconductor IC so as to face eachother; and a step for stacking a first surface of the second resin layerand a back surface of the semiconductor IC so as to face each other. 11.The method for manufacturing a semiconductor IC-embedded substrate asclaimed in claim 10, wherein the semiconductor IC is mounted on thesecond surface of the first resin layer in the first step, based onalignment marks that are formed on the first surface or second surfacethe first resin layer.
 12. The method for manufacturing a semiconductorIC-embedded substrate as claimed in claim 10, wherein the first step isperformed in a state in which a first support substrate is affixed onthe first surface side of the first resin layer.
 13. The method formanufacturing a semiconductor IC-embedded substrate as claimed in claim12, wherein a step for affixing a second support substrate on a secondsurface side of the second resin layer, and a step for peeling the firstsupport substrate from the first surface side of the first resin layerare performed subsequent to the first step and prior to the second step.14. The method for manufacturing a semiconductor IC-embedded substrateas claimed in claim 8, wherein the first step includes: a step forstacking a first surface of the second resin layer and a back surface ofthe semiconductor IC so as to face each other; and a step for stacking asecond surface of the first resin layer and the principal surface of thesemiconductor IC so as to face each other.
 15. The method formanufacturing a semiconductor IC-embedded substrate as claimed in claim14, wherein the semiconductor IC is mounted on the first surface of thesecond resin layer in the first step, based on alignment marks that areformed on the first surface or second surface of the second resin layer.16. The method for manufacturing a semiconductor IC-embedded substrateas claimed in claim 14, wherein the first step is performed in a statein which a second support substrate is affixed on a second surface sideof the second resin layer.
 17. The method for manufacturing asemiconductor IC-embedded substrate as claimed in claim 8, wherein awidth of the wiring pattern on the conductive protrusions is set in thethird step so as to be smaller than a diameter of a protruding portionof the conductive protrusions.
 18. The method for manufacturing asemiconductor IC-embedded substrate as claimed in claim 8, furthercomprising a fourth step for forming a through-electrode that penetratesthrough the first and second resin layers.